Homeostasis is the term given to an organism's ability to regulate internal conditions even when external conditions change
Our bodies work hard to regulate blood glucose concentration, temperature, and water levels
The nervous system consists of the CNS (central nervous system) - the brain and spinal cord, and the PNS (peripheral nervous system) - the nerves that go through the rest of the body
A reflex is when the signal bypasses the brain and goes straight through the spine to the effector, known as a reflex arc
Glands can also be effectors which produce specific chemicals your body needs depending on the situation
The endocrine system is a system of glands that produce or secrete hormones that travel to effectors via the blood
The pituitary gland in your brain can be considered the main or Master gland as it produces hormones in response to stimuli that travel to other glands in your body
The pancreas is involved in making sure that your blood glucose levels aren't too high or too low
Type 1 diabetes is when your pancreas can't produce enough insulin and you have to take insulin injections to do the job instead
Type 2 diabetes is when your cells no longer absorb the glucose as they should
Water balance is maintained by the kidneys filtering the blood to absorb useful substances like glucose and some ions
Anti-diuretic hormone (ADH) is produced in the pituitary gland which travels to the kidneys and causes the tubules in the kidney to reabsorb more water into the bloodstream
Reproduction: Menstruation occurs in females after puberty
FSH (follicle stimulating hormone) causes the neck to mature in the ovary and the ovaries to produce estrogen
Progesterone is also produced by the ovaries which maintains the uterus lining
Contraception options include pills, injections, implants, condoms, diaphragms, and IUDs
IVF (in vitro fertilization) is a method used for couples who have difficulty conceiving naturally
Adrenaline increases heart and breathing rate in stressful situations to prepare the body for fight or flight
Thyroxine controls metabolic rate and is secreted by the thyroid
Plants have their own hormones which can be utilized for growth and development
Gametes are sex cells made through meiosis for sexual reproduction
Variation occurs through meiosis and the swapping of genes between similar chromosomes
An advantage of sexual reproduction is that variation occurs which can result in organisms becoming better suited to their environment
An advantage of asexual reproduction is that only one parent is needed
Some organisms can reproduce both sexually and asexually
Genome is the term given to all the genetic material in an organism, stored in DNA
A gene is a section of DNA that codes for a specific protein
The Human Genome Project completed its initial goal in 2003, mapping out what every gene is responsible for coding
Phenotype is the term given to what code is stored in your DNA, while phenotype is how that code is expressed in your characteristics
Nucleotides are the monomers between the two strands of DNA, made from a sugar and phosphate group (A, T, C, and G)
Every three bases in DNA code for an amino acid
The sequence in DNA is copied by mRNA and taken to a ribosome where amino acids are connected to make a protein
Harmful mutations can change a gene resulting in a protein that doesn't function properly
Some DNA doesn't directly code for proteins but influences how other genes are expressed, known as epigenetics
Characteristics can be controlled by one gene (e.g., color blindness) or multiple genes
Alleles are different types of the same gene, with dominant alleles being expressed over recessive alleles
Human DNA is contained in 23 pairs of chromosomes, with one pair determining sex (XX for female, XY for male)
Variation in organisms is a result of genes inherited from parents and environmental factors
Bacterial resistance is evidence of Darwinian evolution, where mutations lead to increased resistance to antibiotics
Organisms producing fertile offspring are considered of the same species